Segment Reporting - Schedule of Operating Results by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Nov. 30, 2019	Dec. 01, 2018	Nov. 30, 2019	Dec. 01, 2018
Segment Reporting Information [Line Items]
Net Sales	$ 39,634	$ 41,314	$ 80,287	$ 85,471
Gross Profit	12,680	12,971	25,631	26,924
PMT
Segment Reporting Information [Line Items]
Net Sales	29,603	32,328	60,170	67,097
Gross Profit	9,349	10,107	19,028	21,114
Canvys
Segment Reporting Information [Line Items]
Net Sales	7,856	6,498	15,133	13,671
Gross Profit	2,585	2,132	4,906	4,445
Healthcare
Segment Reporting Information [Line Items]
Net Sales	2,175	2,488	4,984	4,703
Gross Profit	$ 746	$ 732	$ 1,697	$ 1,365

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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-Publisher FASB
-Name Accounting Standards Codification
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
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